The Jackie Bradley Jr. story may be an extreme example of how sticking with a struggling player can work out for the best, and his elite defense made the slumps more palatable, but check out some of his long stretches of futility followed by enormous successful stretches:
He came up to MLB with much more hype than Duran has, now. He hit .548 (OPS) in his first two seasons (530 PAs- not 55!). There were many fans screaming for his benching, demotion or worse. Then, on topmof all that, he started the 2015 season hitting .426 through his first 71 PAs (not 55!).
He finished the 2015 season hitting .980 over his last 184 PAs bringing his season OPS to .832. What an example of a manager sticking with a struggling player.
It wasn't over for JBJ: more tests were to come, and maybe that first example led to a longer leash for JBJ than normally afforded to anyone, but again, his great defense helped enormously.
He started the next season off hitting .586 over his first 59 PAs- about the same as Cordero & Renfroe, this year. He then hit 1.191 over his next 144 PAs.
The 2016 season did not start off as badly. (.610 after 65 PAs, but still pretty bad.) Later, he had one of the most memorable hot streaks in Sox history. 1.368 in 95 PAs. He had a .976 OPS on June 25th but had a .720 finish to the season (349 PAs).
Again, in 2017, he started out slowly- hitting .537 in his first 84 PAs. He followed that up with a 1.026 stretch over his next 171 PAs but ended the season at .726 due to a long .596 stretch over his last 210 PAs.
2018 saw Jackie at .502 as late as May 19th! (142 PAs). He finished the season hitting a very respectable .793 over his final 393 PAs.
In 2019, he was still below .400 on April 27th (88 PAs) He was at .553 on May 28th. He then hit 1.060 over his next 118 PAs and finished the season at .738.
He was at .520 in 2020 after 62 PAs, but followed that with a .937 stretch over his last 155 PAs, and signed a big contract to boot.